<div class="problemindexholder" problemindex="B">
 <div class="ttypography">
  <div class="problem-statement">
   <div class="header">
    <div class="title">
     B. Arpa and an exam about geometry
    </div>
    <div class="time-limit">
     <div class="property-title">
      time limit per test
     </div>
     2 seconds
    </div>
    <div class="memory-limit">
     <div class="property-title">
      memory limit per test
     </div>
     256 megabytes
    </div>
    <div class="input-file">
     <div class="property-title">
      input
     </div>
     standard input
    </div>
    <div class="output-file">
     <div class="property-title">
      output
     </div>
     standard output
    </div>
   </div>
   <div>
    <p>
     Arpa is taking a geometry exam. Here is the last problem of the exam.
    </p>
    <p>
     You are given three points
     <span class="tex-span">
      <i>
       a
      </i>
      ,
      <i>
       b
      </i>
      ,
      <i>
       c
      </i>
     </span>
     .
    </p>
    <p>
     Find a point and an angle such that if we rotate the page around the point by the angle, the new position of
     <span class="tex-span">
      <i>
       a
      </i>
     </span>
     is the same as the old position of
     <span class="tex-span">
      <i>
       b
      </i>
     </span>
     , and the new position of
     <span class="tex-span">
      <i>
       b
      </i>
     </span>
     is the same as the old position of
     <span class="tex-span">
      <i>
       c
      </i>
     </span>
     .
    </p>
    <p>
     Arpa is doubting if the problem has a solution or not (i.e. if there exists a point and an angle satisfying the condition). Help Arpa determine if the question has a solution or not.
    </p>
   </div>
   <div class="input-specification">
    <div class="section-title">
     Input
    </div>
    <p>
     The only line contains six integers
     <span class="tex-span">
      <i>
       a
      </i>
      <sub class="lower-index">
       <i>
        x
       </i>
      </sub>
      ,
      <i>
       a
      </i>
      <sub class="lower-index">
       <i>
        y
       </i>
      </sub>
      ,
      <i>
       b
      </i>
      <sub class="lower-index">
       <i>
        x
       </i>
      </sub>
      ,
      <i>
       b
      </i>
      <sub class="lower-index">
       <i>
        y
       </i>
      </sub>
      ,
      <i>
       c
      </i>
      <sub class="lower-index">
       <i>
        x
       </i>
      </sub>
      ,
      <i>
       c
      </i>
      <sub class="lower-index">
       <i>
        y
       </i>
      </sub>
     </span>
     (
     <span class="tex-span">
      |
      <i>
       a
      </i>
      <sub class="lower-index">
       <i>
        x
       </i>
      </sub>
      |, |
      <i>
       a
      </i>
      <sub class="lower-index">
       <i>
        y
       </i>
      </sub>
      |, |
      <i>
       b
      </i>
      <sub class="lower-index">
       <i>
        x
       </i>
      </sub>
      |, |
      <i>
       b
      </i>
      <sub class="lower-index">
       <i>
        y
       </i>
      </sub>
      |, |
      <i>
       c
      </i>
      <sub class="lower-index">
       <i>
        x
       </i>
      </sub>
      |, |
      <i>
       c
      </i>
      <sub class="lower-index">
       <i>
        y
       </i>
      </sub>
      | ≤ 10
      <sup class="upper-index">
       9
      </sup>
     </span>
     ). It's guaranteed that the points are distinct.
    </p>
   </div>
   <div class="output-specification">
    <div class="section-title">
     Output
    </div>
    <p>
     Print "
     <span class="tex-font-style-tt">
      Yes
     </span>
     " if the problem has a solution, "
     <span class="tex-font-style-tt">
      No
     </span>
     " otherwise.
    </p>
    <p>
     You can print each letter in any case (upper or lower).
    </p>
   </div>
   <div class="sample-tests">
    <div class="section-title">
     Examples
    </div>
    <div class="sample-test">
     <div class="input">
      <div class="title">
       Input
      </div>
      <pre>0 1 1 1 1 0<br/></pre>
     </div>
     <div class="output">
      <div class="title">
       Output
      </div>
      <pre>Yes<br/></pre>
     </div>
     <div class="input">
      <div class="title">
       Input
      </div>
      <pre>1 1 0 0 1000 1000<br/></pre>
     </div>
     <div class="output">
      <div class="title">
       Output
      </div>
      <pre>No<br/></pre>
     </div>
    </div>
   </div>
   <div class="note">
    <div class="section-title">
     Note
    </div>
    <p>
     In the first sample test, rotate the page around
     <span class="tex-span">
      (0.5, 0.5)
     </span>
     by
     <img align="middle" class="tex-formula" src="/predownloaded/3b/eb/3beb169548b758ea60b306458d03196407afcd56.png" style="max-width: 100.0%;max-height: 100.0%;"/>
     .
    </p>
    <p>
     In the second sample test, you can't find any solution.
    </p>
   </div>
  </div>
  <p>
  </p>
 </div>
</div>
